Screening apparatus



April 30, 1935. D A WEBER 1,999,673

SCREENING APPARATUS Filed Oct. 9, 1951 @Mi/WI Patented Apr. 30, 1935 UNITED STATES 1,999.67'3 SCREENING APPARATUS Don A. Weber, Fort Wayne, Ina., assignor tu The lDeister Goneentrator Company,;Fort Wayne,

Ind., a corporation. of Indiana4 Application October 9.

11 claims.'

This invention pertainstoscreening apparatus such as is used for classifying 'or grading granular materials. Y

One of' the' objects of this invention is to pro-4 videan apparatus of this vkind with novel means for vibrating the screening medium such that the direction of vibration may be adjusted to suit requirements.

Another object is to provide such apparatus which may be adjusted to impose a different movement on diierent ends of the screen, and to provide for differential vibration.

Another object is to provide such apparatus with vibrating mechanism sov arranged that said mechanism is protected against dust arising from the screening operation. p

Another object is to provide a novel construction for the screening medium such as to render the same adjustable to suit different service requirements.

Further objects will appear from the following description taken in connection with the accompanying drawing, in which:

Figure l is a plan view of a screening apparatus embodying this invention;

Figure 2 isa side view of the same;

Figure 3 is a perspective detail of the construction of the screen;

Figure 4 is a motion diagram of the vibration; and f Figure 5 is a detail of the vibrating mechanism. In the embodiment illustrated in the accompanying drawing, the machine is arranged tov serve as a picker for separating slate from coal or similar operations whereby flat pieces are to be separated from pieces having al cubical or similar shape. The use ofthe machine is not, however, confined to such service but, by the mounting of a screen jacket of a suitable type, may be adapted to practically any type of screening operation.

Referring to the drawing' l designates a suitable base which may be constructed of structural r iron shapes such as channel bars or the like in any suitable manner. Extending upwardly from the base I, is a pair of vertical side plates2`. Journaled in suitable bearings 3' and 4 on the side plates 2 are transverse shafts 5 and E. Each of the shafts 5 and, has mounted Von each end thereof a bell crank l. These bell cranks are in Figure 2 as positioned with one arm horizontal and the other extending vertically downward from the shafts. Arranged to connect the downwardly extending arms of each pair of bell cranks on the same side of the machine is an adjust- 1931, seriar No. 567,799 (C1. 2094425) able link 8. The horizontal Varms of the bell cranks mounted vonthe shaft 5 each has pivoted thereto an adjustable link 9 extending upwardly and pivoted' to a crossl shaft Hl, secured by means of suitable brackets l l to a vibrating frame l2. The horizontal arm of each bell crank 'i on the shaft 6 is similarly connected to a cross shaft I3, which carriesV the lower endV of the vibrating frame IZ. The shafts l'and i3 extend through suitable openings VI4 and l5 in the side plates Z in order to accommodate the vibratory move- Y ment of the frame l2.

The frame l2 may be constructed of channel iron'or other suitable shapes, preferably in rectangular formas illustrated in Figure 1. The screen jacket is mounted torvibrate in this frame.

IThe' screen jacketillustrated in the accompanying drawing is constructed of a series of picker bars I6, extending longitudinally of the jacket. Each bar i6 is equipped with a plurality of attachment brackets il. These brackets may be welded or otherwise secured to the bars I6 at suitable intervals. Each bar It is secured to aV plurality of cross members IIB of `which three are shown in the drawing. The attachment to thecross bar i8 may be made by meansk of a bolt i9, adjustably engaged in a slot 2B; provided in the member i8. AThese cross members i8 may be constructed of metal angles as yillustrated in Figure 3, theslot 2E] being-formed in one ange which extendsv horizontally while the other ange extends downwardly therefrom. The bars I6 are adjustable along the cross members I8 by adjusting. theY bolts i9 along the slots 2l). This provides for adjusting the spacing of the picker bars in order to accommodate the handling of dierent sizes of material. It also provides `for setting vthese bars at a slightly flaring angle with respect to one another toward A the lower end of the screen so as to prevent the lodgment of pieces between the bars.

The screen is supported by two or more tension rods 2l extending lengthwise of the screen and passing through slots 22 arranged vertically in the vertical flanges oi the cross members I8. At the ends of the screen, the bars 2l pass throughV compression springs 23, and then through suitable perforations in the end members of the frame l2. These rods are then secured in place by nuts 24 bearing against the ends of the frame I2. The springs 23 are arranged between the end cross member i8 of the jacket and the end member of the frame l2 at each end of the screen so that the latter is resiliently-suspended in the frame l2. It will be seen that this suspension is resilient in two directions-longitudinally and normally of the plane of the yscreen jacket. g

Adjustably mounted on the side members of the frame i2 are angle members 25. These are arranged with their horizontal flanges secured to the frame i2 and their vertical flanges upstanding along the sides of the screen jacket so as to form guides for the material as it moves down the jacket. The attachment to theV `frame I2 may be made by bolt and slot connections as indicated at 'Z6Y in Figure 1, so as to allow for lateral adjustment of these guides. y

Mounted on a sub-frame 21 on the base I is a vibrating mechanism 28 of any suitable type, driven by a motor 29. The vibratingmechanism 2S may be provided with an oscillating driving rod 3i! of any suitable type. nism issuch as to impose upon the rod 3U a differential Vibration. By differential vibration is meant one in which the characteristics of the movement as regards speed, acceleration and the like are different during opposite strokes.Y As the details of this mechanism form no part of the present invention, a detail description is unnecessary as such mechanisms are well known in the art. A detail description ofsuch a mechanisrn may be found in U. S. Patent No. 1,468,575, issued September 18, 1923 to C. F. Reiff. The particular nature of these vibrations being imposed upon the rod 30 will be transmitted thereby to the screen jacket so that a similar differential form of vibration will be imposed upon the jacket. The particular form of this vibration may be -adjusted to the requirements .of the material handled by .proper selection or adjustment of the vibrating mechanism 28. Accordingly, a screen jacket may be operated with any desired form of vibration, suitable to the material being handled.

The diagram of Figure 4 illustrates such a differential movement. In this diagram the uniform rotary movement of the shaft of the mechanism 2S is plotted horizontally while the corresponding movement of the rod 30 is plotted vertically. It will be noted that on the down stroke of the jacket the movement is at a lower velocity than on the upstroke and that the rapidity. of reversal from up stroke to down stroke is much greater than from the reversal from down stroke to up stroke. Accordingly the screen jacket will have a movement `giving adefinite throw to the material at the end of the up stroke. By suitable adjustment of the mechanism 28, these relations may be varied and if desirable reversed.

Rigidly secured to the shaft 5 and extending downwardly therefrom is an arm 3| pivoted at 32 to the oscillating rod 3G. There is also pivoted to the arm 3i at 33, a rod 34 tensioned by a spring 35 bearing against a bracket 36 on the sub-frame 2. The spring 35 tensions the arm 3| in a direction opposite to the pull of the rod 30. Accordingly the operation of the vibrating mechanism 28 will oscillate the arm 3l and, therefore, the shaft 5. Oscillation ofthe shaft 5 causes angular oscillation of the bell cranks 'l attached thereto, and these in turn acting through the links 8 oscillate the bell cranks on the shaft 6 in a similar manner. The bell cranks 1, through their connections to the frame l2, will cause said frame to vibrate in an up and down direction in response to the oscillations of the shaft 5. The up and down movement of the frame l2 will cause the screen jacket to vibrate in said frame in a direction no1"- This mechamal to the Yplane of said jacket. This movement causes the material moving over the screen to be thrown up in rapid vibration and as the screen inclines downwardly towards its discharge end the material is thereby caused to move along the screen. During this movement at pieces thin enough to pass between the bars dropthrough the screen, while the remaining material travels down to the discharge end thereof.

Mounted between the side plates 2 and below 'the vibrating screen is a chute 31 adapted to receive the material that falls through the screen and convey it-to a suitable receptacle (not shown). The chute 31 vis built over and encloses the vibrating mechanism, including the spring 35, the arm 3| and its connections to the mechanism 28. These parts are, therefore, protected against the material passing through the screen and the dust arising therefrom.

It will be noted that there are no rotating bearings on` this machinev'outside of the mechanism 28. All the other bearings involved are pivotal or slightly oscillating bearings such as are subject to very little wear. All bearings requiring continuous lubrication are conned to the mechanism- 28, which may be completely enclosed against the entrance of dust to its bearings, so that adequate lubrication may be supplied and the bearings thereby protected against excessive wear.

The bell cranks 'l are mounted for adjustment on the shafts 5 and 6 in any suitable manner. This may be accomplished'by securing each bell crank to the shaft by a set screw 39 orrthe like so that its angular position may be changed at will. Any other type of `connection capable of such adjustment may, of course, be used. By adjusting the angular positions of the bell cranks '1, the direction of movement of the frame I2 may be altered at will, thus a movement directly at right angles tothe plane of the screen jacket may be employed or by proper adjustment such movement may be more nearly vertical or more nearly horizontal.

By adjustment of the link 8, the relative positions of the bell cranks on the shafts 5 and 6 may be changed so that if desired, the upper and lower ends of the screen jacket may be given movement in different directions.

The inclination of the screen jacket may be adjusted by adjusting the length of the link 9. It will be seen thatY this invention provides a simple and robust construction for screening apparatus of this type. While the vibration imposed upon the screen jacket is generally in a direction substantially normally to the plane of the jacket, such direction may be altered by adjustment of the bell cranks so as to give the screen a throw which is more nearly vertical or more nearly horizontal. This is an important feature in a screen of this type, in which a screening medium vibrates substantially normally of its plane. By control of the particular direction of movement of the screen, the travel of the material over the screen may be controlled. Furthermore, the direction fof throw may also be made use of torrefiect Vthe manner `in which` the material is made to pass through the screen. As a Wide range of adjustment is provided, a corresponding range of control is possible. v ,Y

The construction of the screen jacket itself as illustrated in the accompanying drawing has the advantage of being adjustable to various sizes of material, and also to provide in a, simple manner for the removal of bars which mayv become Worn. The provision of the cross members I8 not only provides for rigid spacing of the bars, but the middle cross member may in certain cases be arranged to strike a suitable abutment 38 mounted below the frame l2 so as to provide a bumping action which will assist in working the material through the screen.

While this apparatus has been described as a unitary machine, it is obvious that various individual features or sub-combinations thereof may be useful by themselves without reference to the other features of the machine. It is understood that the employment of such individual features or sub-combinations is contemplated by this invention and Within the scope of the appended claims. It is further obvious that various changes may be made in the details of construction Within the scope of the appended claims Without depart ing from the spirit of this invention. It is understood, therefore, that the invention is not limited to the specic details sho-Wn and/or described.

Having thus described the invention, what is claimed is:

1. Screening apparatus of the character described, comprising, a screen frame, a screen jacket mounted therein for vibration as a Whole longitudinally and normally of its plane, bellcranks connected to support the head and foot ends of said frame, connections between said bell-cranksto control their relative movements, means for adjusting said bell-cranks relatively to each other, vibrating mechanism, and operating connections from said mechanism to said bell-cranks adapted to vibrate said jacket with dierent movements at kits head and foo-t.

2. Screening apparatus of the character described, comprising, a screen frame, a screen jacket mounted for vibration in said frame having a plurality of supporting rods extending longitudinally cf said frame, a plurality of picker bars, cross members extending transversely of said jacket and secured to said bars, means for resiliently mounting said cross members on said rods, and means for vibrating said jacket.

3. Screening apparatus of the character described, comprising, a screen frame, a screen jacket mounted fcr vibration in said frame hav--v ing a plurality of supporting rods extending longitudinally of said frame, a plurality of picker bars, cross members extending transversely of said jacket and secured to said bars for adjustment therealong, means for resiliently mounting said cross members on said rods, and means for vibrating said jacket.

4. Screening apparatus of the character described, comprising, a screen frame, a screen jacket mounted for vibration in said frame having a plurality of supporting rods extending longitudinally of said frame, a plurality of picker bars, cross members extending transversely of said jacket and secured to said bars, means for resiliently mounting said cross members on said rods including springs on said rods between said cross members on said frame, and means for vibrating said jacket.

5. Screening apparatus of the character described, comprising, a screen frame, a unitary screen jacket resiliently suspended in said frame for vibration as a Whole along and normally of its plane, means supporting said frame near both ends thereof adapted to vibrate the same in a direction angular to its plane, means for controlling the direction or" action of said vibrating means, and means for operating said vibrating means.

6. Screening apparatus of the character described, comprising, a screen frame, a screen jacket having a plurality of longitudinally extending laterally spaced picker bars mutually interconnected to form a unitary jacket, said jacket being resiliently suspended in said frame for vibration as a Whole along and normally of its plane, means supporting said frame near both ends thereof adapted. to vibrate the same in a direction angular to its plane, means for controlling the direction of action of said vibrating means, and means for operating said vibrating means.

'7. Screening apparatus of the character described, comprising, a screen frame, a unitary screen jacket resiliently suspended in said frame for vibration as a Whole along and normally of its plane, means supporting said frame near both ends thereof adapted to vibrate the same in a direction angular to its plane, means for independently controlling the direction of action f said vibrating means at opposite ends of said frame, and means for operating said vibrating means.

8. Screening apparatus of the character described, comprising, a screen frame, a plurality of picker bars, means for adjustably securing said bars together to form a unitary jacket, resilient means formounting said jacket in said frame for vibration at an angle to the plane of the jacket, and means for vibrating said jacket.

9. Screening apparatus of the character described, comprising, a screen frame, a plurality of picker bars, means for adjustably securing said bars together to form a unitary jacket, resilient means for mounting said jacket in said frame for vibration at an angle to the plane of the jacket, and means for vibrating said jacket adjustable to vary the direction of vibration.

10. In a screening apparatus of the character described, a screen jacket comprising, a plurality of longitudinally extending supporting rods, a plurality of picker bars, cross members extending transversely of the jacket and secured to said bars, and means for resiliently mounting said cross members on said rods.

11. In a screening apparatus of the character described, a screen jacket comprising, a plurality of longitudinally extending supporting rods, a plurality of picker bars, cross members extending transversely of the jacket and secured to said bars, and means for resiliently mounting said cross members on said rods and for resiliently supporting said rods.

- DON A. WEBER, 

